Bullet Casting Woes

[villiers]

Just two further queries .... I cast bullets from a Hensold mould made to a Serrosafe casting of the barrel, chamber and muzzle end. If I used a sizer, would it change the calibre so that it no longer suited my specific barrel? And secondly, if I load the original amount of BP, there´s no space left for lube under the bullet. Even using a bit less powder, the bullet compresses the powder ... or ... the round comes out too long and the breechblock won´t close on the base of the cartridge. Should I use a compression die to get all the powder into the cartridge?

[Patrick Chadwick]

I cast bullets from a Hensold mould made to a Serrosafe casting of the barrel, chamber and muzzle end.

If you sent him a Cerrosafe casting, Hensold will have made the mould so that the cast bullet is correct without sizing. Ask him if you are not sure.

If I used a sizer, would it change the calibre so that it no longer suited my specific barrel?

If you size down any more than a thou or so (i.e. just enough to smooth the surface) then the bullet will be a trifle undersized. But soft-lead bullets can bump up several thou to fit a bore, so the diameter is not nearly as critical as for jacketed bullets. You should be using something like max. 5% tin in a tin-lead alloy. Anything higher is an expensive waste of tin, anything with type metal is instantly too hard, and anything with wheelweights is unpredictable scrap. Lead flashing (i.e. roofing lead) with 8% eutectic (electronics) solder added is a simple answer that provides consistent performance. Your bullets should (almost) all cast out at about plus/minus 2gn of the average value. Anything outside that range should go back into the pot as having voids, lumps of slag etc. Then classify the bullets into two classes, each with a spread of 2gn. For a long-range competition you can select classes with a spread of 1gn, but I doubt that you will see any significant difference at 100 meters.

Should I use a compression die to get all the powder into the cartridge?

No, compression seems to make the vivacity inconsistent. Just adapt the amount of BP to what you can get in as a charge when the powder is well shaken down. You must have the lubricant, with an amount as I explained in a previous post. The original "service" charge is effectively a theoretical maximum.

[villiers]

Ok ... thanx Patrick. The old BP must have had a considerably greater volume per unit of weight than Swiss No. 2. I was thinking of maybe using a sizer (just `cos the bullets look nicer) and then paper patching the bullets. In warm weather, the lube under the bullet really does contaminate the top layer of BP, even though I use a very thin cork patch that fits tightly between the bullet and the lube, AND between the lube and the powder. I now seat the bullets shortly before going to the range. The spread of bullet weights definitely is a b*gger.

[Patrick Chadwick]

I now seat the bullets shortly before going to the range.

So do I. For the very same reason. A greasy lubricant will always penetrate the wad, eventually. Pure wax would probably last a very long time, but greases have lighter fractions that soak through the wad material - quite fast in warm weather, as you have discovered.

But what bothers me more is the variation in bullet weight you are observing. What is the variation?

The first few casts in a session will usually show sub-optimal filling of the mould, and be underweight. The very last casts, really getting down to the bottom of the pot, will also be dubious, maybe embedding some crud off the bottom of the pot. And any flashing on the cast indicates that the mould was not quite closed, and the bullet is likely to be noticeably overweight. But the main flow should be within the sort of range I quoted. However, you must keep on casting at a steady rate, not stopping for tea and then restarting, so that the mould keeps a constant temperature. If your arms are aching and you need a break, park the mould over the melt - as close the to melt as you can get it, without dunking it. This helps to maintain a good working temperature.

Try to pour at a constant rate, and have a similar quantity of lead as the blob on top of the cut-off plate each time , so that the final fill as the lead in the mould shrinks and draws in material from the reservoir of the blob is also fairly constant. In short, every part of the operation should be as consistent as possible.

[jmoore]

Try to pour at a constant rate, and have a similar quantity of lead as the blob on top of the cut-off plate each time , so that the final fill as the lead in the mould shrinks and draws in material from the reservoir of the blob is also fairly constant.

I think that continuing to pour well after it overflows may be one big reason the weight variation has been so small for my casts lately. Used to strive for a nice neat blob on top, but now just keep the faucet on for a while whilst moving the mould about a tiny bit. Couldn't believe the last good production session where most bullets were within one tenth grain! Had to recheck the scales more than once... But after going back to one of the old Lyman manuals, it was noticed that there's at least one large photo within that showed a similar technique: Lots of overflow. Perhaps the continued flow keeps the bullet metal agitated and allows air to escape before the small sprue hole solidifies. The overflow is collected in a tiny cast iron skillet in my case. (See photo in Post #1.) Guessing that the amount is about equal to the weight of the bullet or a bit more. It's annoying to drain the pot faster than normal, but the results seem to be encouraging.

[jmoore]

Here's an odd question: Do you think having little to no play on one side of the mould/handle assembly would lead to dramas? Have drilled the cross hole after thinning the plate from 0.312" to 0.307" (in order to keep the mould from being a press fit onto the jaw), but did the job with the handle shut tightly. So one side has pretty much no wiggle.

The assembly opens and closes well enough. But will the lack of wiggle make dislodging bullets more difficult? Trying to keep things as stable as possible, as the repaired jaw must be on the sprue plate attachment side as the added width makes having the repair on the non-impact absorbing "clean half" impractical.

[villiers]

This whole casting business is turning into rocket science. I´ve not tried it on a full moon etc. but re-melting the duds is no great bother. Can now get most rounds into the standard 10 inch German paper target at 300 metres and even (sometimes) some quite good groups. Think that might be coming up to my limitations, though the Werder could well be better.

[jmoore]

Can now get most rounds into the standard 10 inch German paper target at 300 metres and even (sometimes) some quite good groups. Think that might be coming up to my limitations, though the Werder could well be better.

At this point, could it be the Werder's sights that's the major limitation? 3+ MOA at longish carbine distance seems pretty good.

[gsimmons]

When throwing the duds back in the pot, I wait until I'm done casting, because they will cool the pot too much while you're casting. I cast mostly .58 minies and really makes a difference.

[villiers]

At this point, could it be the Werder's sights that's the major limitation? 3+ MOA at longish carbine distance seems pretty good.

I expect, at this point, it might well be ... ME. I´m looking around for someone who´s a bit better, but the others at the range stay at max. 100 metres with arm long telescopic lenses so they´re not much help. The Werder (and me) are not all that much worse than me with the LE No. 5.